The PI proposes to study the metabolism of chitin and its derivatives in Vibrio furnissii and in E. coli. Chitin is a major component of the carbon cycle in aquatic biospheres, yet does not accumulate to high levels because of the high activity of chitin degrading microorganisms. The specific aims of this project are to define the reactions involved in the cleavage of the chitin disaccharide N,N diacetyl chitobiose in E. coli and V. furnissii, to characterize the presumptive V. furnissii chitiporin, and to determine whether V. furnissii expresses a cell- associated chitinase in addition to its extracellular chitinase.